It is known to grind electrodes. This is commonly effected manually with open grinding or separating wheels. Such methods are imprecise and dangerous. Furthermore, there are devices with open grinding wheels where the welding electrodes are guided through a guiding sleeve with a certain angle relative to the grinding wheel. Such devices are also expensive. In particular, it is expensive to adapt such a device to various types of welding electrodes or for different tips or cutting shapes. In particular, this requires a time-consuming exchange of the guiding sleeves.
A device where electrodes can be produced with a plurality (for example 6) of different electrode diameters with a plurality of different tip angles (for example 4) with many lengths is a valuable, cost-saving aid.
DE 100 10 520 A1 discloses a device for grinding welding electrodes with a grinding wheel. The grinding wheel rotates in a grinding wheel housing. The device is provided with an additional housing portion which is adapted to be fixed to the grinding wheel housing and which is provided with at least one opening for guiding a welding electrode for grinding in a defined position relative to the grinding wheel. The plane of the grinding wheel is essentially the separating plane between the grinding wheel housing and the additional housing portion. The additional housing portion can be provided with a plurality of adjacent, different openings for receiving different kinds of welding electrodes. The additional housing portion can, however, also be provided with a plurality of adjacent openings having an axis cutting the plane of the grinding wheel under different angles. A radial slit can be formed in the grinding wheel housing extending along the front end of the housing, which is used to pass a welding electrode for cutting at the outer perimeter of the grinding wheel. The grinding wheel of the disclosed device is fixed to a grinding wheel reception which in turn is connected to a driving shaft of a driving motor. The entire device forms a portable unit.
DE 102 43 210 B3 discloses an assembly where two parallel grinding wheels with different grain sizes are used. A first grinding wheel rotates in a space between the motor unit and a first housing portion. The second grinding wheel rotates in a second space between the first housing portion and the second housing portion. The housing portions are provided with openings for guiding the welding electrodes. The known assembly enables the use of different grinding wheels with standard diameters without the need of an exchange.
Further to a motor in a motor unit the assembly makes use of further housing portions: a motor flange directly screwed to the motor unit and at least one housing portion provided with openings for guiding the electrodes. The openings extend from the side of the housing portion opposite to the motor in the direction of the grinding wheel rotating between the motor flange and the housing portion. Depending on the amount of grinding wheels further housing portions are added. Here also the openings extend from the side opposite the motor. In other words: The electrodes are always inserted into the openings in a direction towards the motor. Depending on the amount of housing portions the assembly is relatively long and requires a long driving shaft. Several fixing elements, such as screws, nuts, pins etc. are required for fixing the housing portions.
DE 10 2006 052 905 A1 discloses a device for grinding electrodes where the opening is provided in a housing portion which is directly connected to the motor housing and the grinding wheel is provided at the side of the housing portion remote from the motor, and wherein the opening extends from the circumference of the housing portion towards the grinding wheel. The first housing portion which is provided with openings also serves as motor flange and is directly provided at the motor housing. The electrodes are inserted away from the motor into the openings. The grinding wheel is positioned on the side remote from the motor. With such an assembly, the assembly is shorter by the length of one component. The assembly requires less housing portions and fixing components and the shafts can be shorter. Thereby, the risk of undulating of the shaft is reduced.
It is disadvantageous, however, with the use of the motor flange as a housing portion for the bore holes that it is difficult to be exchanged. The bearing for the motor shaft is arranged in this component. If a bore hole has defects and the motor flange must be exchanged the bearing must also be exchanged. For this purpose the motor must be disassembled and newly balanced. This is time consuming. Usually, the device is sent to the manufacturer for the exchange of the motor flange. Then, the device is not available for the user in the meantime.